Watercraft

ABSTRACT

A watercraft with a tunnel providing one or more aerodynamic lifting surfaces, together with stabilizing fins in the form of hydroplanes or hydrofoils, and propulsion means aligned with the stabilizing fins. The combined effect of the lifting surfaces and stabilizing fins lifts the craft to reduce hydrodynamic resistance and provides enhanced roll and pitch stability. In a preferred form, the tunnel has two lifting surfaces in tandem, each surface being curvilinear and sloping downwardly and aftwardly at its rearward portion. Hydrofoils and hydroplanes are provided on the bottoms of the outer sponsons and an additional hydrofoil is mounted on an enlarged central forward portion of the hull. One propulsion means is mounted at the after end of the forward central hull portion and the other two at the after end of the sponsons, the hull propulsion means being aligned with the stabilizing fins.

United States Patent [191 Szpytman Mar. 18, 1975 WATERCRAFT [76]Inventor: Jack J. Szpytman, 910 N. Brys Dr., Grosse Pointe Woods, Mich.48236 [22] Filed: July 16, 1973 [21] Appl. No.: 379,333

[52] U.S. Cl ll4/66.5 R, l14/66.5 H, 115/67 R [51] Int. Cl B63b l/30[58] Field of Search 1l4/66.5 R, 66.5 H, 66.5 P,

' ll4/66.5 F, 67 A, 61

Primary ExaminerRobert J. Spar Assistant-ExaminerDonald W. UnderwoodAttorney, Agent, or Firm-Harness, Dickey & Pierce [57] ABSTRACT Awatercraft with a tunnel providing one or more aerodynamic liftingsurfaces, together with stabilizing fins in the form of hydroplanes orhydrofoils, and propulsion means aligned with the stabilizing fins. Thecombined effect of the lifting surfaces and stabilizing fins lifts thecraft to reduce hydrodynamic resistance and provides enhanced roll andpitch stability. In a preferred form, the tunnel has two liftingsurfaces in tandem, each surface being curvilinear and slopingdownwardly and aftwardly at its rearward portion. Hydrofoils andhydroplanes are provided on the bottoms of the outer sponsons and anadditional hydrofoil is mounted on an enlarged central forward portionof the hull. One propulsion means is mounted at the after end of theforward central hull portion and the other two at the after end of thesponsons, the hull propulsion means being aligned with the stabilizingfins.

13 Claims, 5 Drawing Figures a" a 1; cicadas]: [113:1 27 g z z r WWW/[=7mama a Y it n WATERCRAFT BACKGROUND OF THE INVENTION The inventionrelates to watercraft of the type utilizing aerodynamic forces createdduring motion to lift the craft at least partially out of the water,thus reducing the wetted surface and spray resistance, and increasingspeed. The application is related to my US. Pat. No. 3,702,598 issuedNov. 14, 1972 and entitled Watercraft as well as to my application Ser.No. 205,017 filed Dec. 6, 1971.

BRIEF SUMMARY OF THE INVENTION use of mechanical systems.

It is another object to provide a watercraft of this nabulkhead 29.These compartments are utilizable for cargo purposes. If, for example,the watercraft is being used as a car ferry, vehicles 29 may be storedin these compartments, a ramp 31 being indicated partially in FIG. 1 forloading and unloading through an access opening 32.

ture having improved lateral or roll stability and which minimizes anytorque effect on the hull caused by a vertical moment arm between theengine thrust and the stabilizing fins which might adversely affect theattitude of the vessel.

It is another object to provide an improved watercraft having thesecharacteristics, in which prow and keel means are provided forprotecting the hydrofoils from damage, acting as skirts for containingthe air cushion and housing the hydrofoil adjusting means.-

Briefly, the watercraft of this invention comprises an elongated hull,an undersurface on said hull having a concavely curved aerodynamiclifting shape configured to provide an upwardly acting force applied tosaid craft in response to flow of air therealong, stabilizing fin meanscarried by laterally spaced portions of said hull below said aerodynamiclifting surface, and propulsion means carried by said hull.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view,partly in section, showing a watercraft incorporating the principles ofthis invention.

FIG. 2 is a bottom plan view thereof.

FIG. 3 is a cross-sectional view in elevation taken along the line 3-3of FIG. 2.

FIG. 4 is an enlarged fragmentary detailed view of one of the hydrofoilsand its adjusting mechanism.

FIG. 5 is an enlarged fragmentary cross-sectional view in elevationtaken along the line 5-5 of FIG. 1 showing the construction of one ofthe hydroplanes.

DESCRIPTION OF THE PREFERRED EMBODIMENT The watercraft is generallyindicated at 11 and comprises an elongated hull generally indicated at12, the major portion of which is of rectangular shape in plan, as bestseen in FIG. 2. Above the at-rest water line 13, hull 12 is providedwith sides 14 which extend upwardly as shown in FIG. 3 and then slopeinwardly, being joined by a cabin top 15 at their upper ends.Compartments l6, l7 and 18 are formed between top 15 and a deck 19, thecompartments being separated by longitudinal bulkheads 21 and 22. Thesethree compartments may be utilized for passenger purposes, lights 23,seats 24 and tables 25 being shown for this purpose. A second deck 26extends between sides 14 below deck 19 with the space therebetween beingdivided into compartments 27 and 28 by a longitudinal The forwardportion 33 of hull 12 is tapered and flared as seen in FIGS. 1 and 2.Hull portion 33 is deeper than the remainder of the hull (except for thesponsons to be described later) and its underside 34 is provided withahydrofoil 35. The construction of the hydrofoil is seen best in FIGS.1, 2 and 4. The hydrofoil is disposed within a recess 36 in hull bottom34 and is pivoted at its forward end as indicated at 37. The hydrofoilis of airfoil shape and is actuatable between a recessed or cruisingposition shown in solid lines in FIG. 4 and a takeoff position shown indot-dash lines. The solid line position is within recess 36 whereas thetakeoff position has a greater angle of incidence to achieve added lift.

The means for actuating hydrofoil 35 may comprise a reciprocable fluidactuated motor 38 or other appropriate means disposed within hullportion 33.

Propulsion means in the form of a jet drive 39 is carried by hull bottom34 rearwardly of and aligned with hydrofoil 35. The jet drive has awater intake 41 seen in FIG. 1. Alternative propulsion means such as apropeller could be used.

The hull bottom rearwardly of bottom portion 34 is generally indicatedat 42 in FIG. 1 and comprises a pair of aerodynamic lifting surfaces 43and 44 in tandem. The curvilinear shape of these surfaces is similar tothat shown in my above-mentioned US. Pat. No. 3,702,598, each surfacehaving an upwardly and aftwardly extending forward portion, a generallyhorizontal intermediate portion and a downwardly and aftwardly extendingrearward portion. These portions are smoothly blended into an airfoilshape to provide surfaces which will impart substantial lifting forcesto the craft when in movement, due to the air cushion effect. Bottom 42has an intermediate portion 45 between surfaces 43 and 44 and an afterportion 46. Portions 45 and 46 are flat lifting surfaces which blendsmoothly with the aerodynamic surfaces immediately forwardly thereof.

Re-entrant portions 47 and 48 are formed at the forward ends of surfaces43 and 44 respectively. The pockets created by these surfaces willtendto trap air and prevent it from escaping forwardly. Optionally, blowers49 and 51 may be provided for delivering air to pockets 47 and 48respectively. The combined effect of the pockets and blowers willcounteract accumulated air cushion backup and assist in creating airbuildup.

A pair of sponsons generally indicated at 52 are provided along oppositesides of the craft to form, together with bottom portion 42, a tunnel toentrap air which will actagainst aerodynamic surface 42. Sponsons 52extend from the after end of hull portion 33 to the after end of thevessel and have faired bow portions 53 indicated in FIG. 1. The upperportions of the sponsons have outer side walls 54 contiguous with sides14 and inner side walls 55, but the lower portions 56 are tapered tothin cross sections for lateral stability, as seen in FIG. 5. Flangetype hydroplanes 57 are mounted along the bottoms of the sponsons. Theshape of these hydroplanes is seen in FIG. 2, the hydroplanes graduallyflaring in an after direction. These hydroplanes extend along a majorportion of the sponsons and a pair of jet drives 58 are mounted in theafter ends of the sponsons, the jet drives being aligned with thehydroplanes. These jet drives have water intakes 59 (FIG. 2), Jet drives58 as well as drives 39 are provided with rudders 60 and 61 respectivelymounted adjacent thereto.

A pair of hydrofoils 62 are mounted under the forward ends of sponsons52 as seen in FIGS. 1 and 2. These hydrofoils are shaped similarly tohydrofoil 35 and are pivoted at their forward ends for movement fromcruising positions within sponson recesses to lower or takeoffpositions. Reciprocable motors 63 are provided for hydrofoils 62. Thehydrofoils are aligned with hydroplanes 57 and thus with jet drives 58.

A keel member 64 extends centrally along bottom 42, the keel beingdirectly under bulkhead 29. An airflow control leveler 65 is mounted atthe after end of the vessel contiguously with flat surface 46, thisleveler being actuatable by a reciprocable motor 66 to control theamount of air flow.

In operation, movement of the craft along the water will cause it torise due to the combined effects of the stabilizing fins (hydroplanesand hydrofoils) and aerodynamic surface 42. The craft will rise so thatthe water line will be as indicated at 67 in FIGS. 1 and 3. The takeoffpositions of hydrofoils 35 and 62 will facilitate rising'of the craft,after which the hydrofoils may be retracted to their cruising positions.Sponsons 54 will act to protect the hydrofoils from damage, as skirtsfor containing the air cushion impacting aerodynamic surface 42, and aslateral stabilizing means. Hydroplanes 57 will increase the lateralstability of the craft as well as contributing to the lifting action.

Because ofthe alignment of propulsion means 39 and 58, with thestabilizing fins (hydrofoils and hydroplanes) there will be little, ifany, torque tending to affect the attitude of watercraft 11. This willfacilitate keeping it on an even keel.

I claim:

1. A watercraft comprising an elongated hull, an under surface on saidhull having a concavely curved aerodynamic lifting shape configured toprovide an upwardly acting force applied to said craft in response toflow of air therealong, stabilizing fin means carried by laterallyspaced portions of said hull below said aerodynamic lifting surface,each of said last-mentioned hull portions carrying said stabilizing finmeans at its lower end, each of said stabilizing fin means having agenerally flat horizontal lateral configuration in cross section withexposed downwardly facing and upwardly facing surfaces extendinglaterally outwardly on opposite sides of said lower end, and propulsionmeans carried by said hull, said aerodynamic lifting surfaces comprisingtwo concave surfaces in tandem, each surface comprising an upwardly andaftwardly extending forward portion, a substantially horizontalintermediate portion, and a downwardly and aftwardly extending rearwardportion, a flat surface being provided on the underside of the hullbetween said two aerodynamic sections.

2. The combination according to claim 1, said stabilizing fin meanscomprising a single pair of elongated hydroplanes fixed to sponsons onopposite sides of said lifting surface and extending along majorportions of said sponsons.

3. The combination according to claim 1, said stabilizing fin meanscomprising a pair of hydrofoils movably mounted on opposite sides ofsaid surface, and means for moving said hydrofoils between uppercruising positions and lower takeoff positions.

4. The combination according to claim 1, said propulsion meanscomprising a pair of propulsion units on opposite sides of said hullaligned with said stabilizing fin means.

5. The combination according to claim 4, said stabilizing fin meanscomprising aftwardly flared hydroplanes extending along the bottoms ofsponsons on opposite sides of said surface.

6. The combination according to claim 5, said hull having a relativelydeep forward portion, said stabilizing fin means further comprising ahydrofoil movably mounted beneath said forward hull portion, means formoving said hydrofoil between an upper cruising position and a lowertakeoff position with a greater angle of incidence, and a propulsionunit carried by the after end of said forward hull portion and alignedwith said hydrofoil.

7. The combination according to claim 1, further provided with a pair ofrelatively thin elongated sponsons along opposite sides of said hull,the forward ends of said sponsons being faired, said stabilizing finmeans comprising a pair of hydrofoils pivotally mounted at their forwardends beneath said sponsons, said sponsons acting as skirts forcontaining the aircushion formed beneath said craft and impinging onsaid aerodynamic surface, reciprocable motor means within said sponsonsconnected to said hydrofoils for moving them between upper cruisingpositions and lower takeoff positions, and recesses in said sponsons forreceiving and protecting the hydrofoils when in cruising position.

8. The combination according to claim 7, said propulsion means beingcarried by the after ends of said sponsons and being aligned with saidhydrofoils.

9. The combination according to claim 8, the lower portions of saidsponsons having relatively thin cross sections for lateral stability,said stabilizing fin means further comprising flange type hydroplanesfixed to the undersides of said sponsons and extending therealong.

10. The combination according to claim 1, the forward ends of said twoaerodynamic lifting surface sections being reentrantly formed to providepockets which tend to trap air so as to prevent the air from escapingforwardly.

11. The combination according to claim 10, further provided with blowerswithin said hull with their outlets connected to said last-mentionedpockets to counteract accumulated air cushion backup.

12. A watercraft comprising an elongated hull having a major portion ofgenerally rectangular shape in plan and a forward tapered hull portion,said forward hull portion being deeper than the remainder of the hull, ahydrofoil pivotally mounted in a recess beneath said forward hullportion, reciprocable motor means within said forward hull portion foractuating said hydrofoil between an upper cruising position and a lowertakeoff postion, propulsion means carried by the after end of saidforward hull portion in alignment with said hydrofoil, an aerodynamiclifting surface on the underside of the main hull portion, said liftingsurface having two sections in tandem, each section having an upwardlyand aftwardly extending forward portion, a substantially horizontalintermediate portion and a downwardly and aftwardly sloping rear portionwith the portions being blended together to provide a concavecurvilinear surface creating an upwardly acting aerodynamic force inresponse to flow of air therealong, a pair of sponsons extendingdownwardly on opposite sides of said hull alongside said lifting surfaceto form a tunnel therewith, a pair of hydrofoils pivotally mounted inrecesses under the forward ends of said sponsons, reciprocable motormeans within said sponsons for moving said last-mentioned hydrofoilsbetween cruising and takeoff positions, fixed flange type hydroplanessecured to the undersides of said sponsons and extending therealong inalignment with said last-mentioned hydrofoils, and a pair of propulsionunits at the ends of said sponsons and in alignment with saidhydroplanes.

13. A watercraft comprising an elongated hull, an undersurface on saidhull having a concavely curved aerodynamic lifting shape configured toprovide an upwardly acting force applied to said craft in response toflow of air therealong, stabilizing fin means carried by laterallyspaced portions of said hull below said aerodynamic lifting surface,each of said last-mentioned hull portions carrying said stabilizing finmeans at its lower end, each of said stabilizing fin means having agenerally flat horizontal lateral configuration in cross section withexposed downwardly facing and upwardly facing surfaces extendinglaterally outwardly on opposite sides of said lower end, and propulsionmeans carried by said hull, said aerodynamic lifting surface comprisinga plurality of surface sections extending from front to rear eachsurface section comprising an upwardly and aftwardly sloping forwardportion, a substantially horizontal intermediate portion, and adownwardly and aftwardly sloping rearward portion, said surface sectionsbeing longitudinally aligned with one another and located between saidlaterally spaced hull portions, with said portions being blendedtogether in curvilinear fashion and each surface section connected withthe preceding surface section by a substantially horizontal intermediatesection.

1. A watercraft comprising an elongated hull, an under- surface on saidhull having a concavely curved aerodynamic lifting shape configured toprovide an upwardly acting force applied to said craft in response toflow of air therealong, stabilizing fin means carried by laterallyspaced portions of said hull below said aerodynamic lifting surface,each of said last-mentioned hull portions carrying said stabilizing finmeans at its lower end, each of said stabilizing fin means having agenerally flat horizontal lateral configuration in cross section withexposed downwardly facing and upwardly facing surfaces extendinglaterally outwardly on opposite sides of said lower end, and propulsionmeans carried by said hull, said aerodynamic lifting surfaces comprisingtwo concave surfaces in tandem, each surface comprising an upwardly andaftwardly extending forward portion, a substantially horizontalintermediate portion, and a downwardly and aftwardly extending rearwardportion, a flat surface being provided on the underside of the hullbetween said two aerodynamic sections.
 2. The combination according toclaim 1, said stabilizing fin means comprising a single pair ofelongated hydroplanes fixed to sponsons on opposite sides of saidlifting surface and extending along major portions of said sponsons. 3.The combination according to claim 1, said stabilizing fin meanscomprising a pair of hydrofoils movably mounted on opposite sides ofsaid surface, and means for moving said hydrofoils between uppercruising positions and lower takeoff positions.
 4. The combinationaccording to claim 1, said propulsion means comprising a pair ofpropulsion units on opposite sides of said hull aligned with saidstabilizing fin means.
 5. The combination according to claim 4, saidstabilizing fin means comprising aftwardly flared hydroplanes extendingalong the bottoms of sponsons on opposite sides of said surface.
 6. Thecombination according to claim 5, said hull having a relatively deepforward portion, said stabilizing fin means further comprising ahydrofoil movably mounted beneath said forward hull portion, means formoving said hydrofoil between an upper cruising position and a lowertakeoff position with a greater angle of incidence, and a propulsionunit carried by the after end of said forward hull portion and alignedwith said hydrofoil.
 7. The combination according to claim 1, furtherprovided with a pair of relatively thin elongated sponsons alongopposite sides of said hull, the forward ends of said sponsons beingfaired, said stabilizing fin means comprising a pair of hydrofoilspivotally mounted at their forward ends beneath said sponsons, saidsponsons acting as skirts for containing the air cushion formed beneathsaid craft and impinging on said aerodynamic surface, reciprocable motormeans within said sponsons connected to said hydrofoils for moving thembetween upper cruising positions and lower take- off positions, andrecesses in said sponsons for receiving and protecting the hydrofoilswhen in cruising position.
 8. The combination according to claim 7, saidpropulsion means being carried by the after ends of said sponsons andbeing aligned with said hydrofoils.
 9. The combination according toclaim 8, the lower portions of said sponsons having relatively thincross sections for lateral stability, said stabilizing fin means furthercomprising flange type hydroplanes fixed to the undersides of saidsponsons and extending therealong.
 10. The combination according toclaim 1, the forward ends of said two aerodynamic lifting surfacesections being reentrantly formed to provide pockets which tend to trapair so as to prevent the air from escaping forwardly.
 11. Thecombination according to claim 10, further provided with blowers withinsaid hull with their outlets connected to said last-mentioned pockets tocounteract accumulated air cushion backup.
 12. A watercraft comprisingan elongated hull having a major portion of generally rectangular shapein plan and a forward tapered hull portion, said forward hull portionbeing deeper than the remainder of the hull, a hydrofoil pivotallymounted in a recess beneath said forward hull portion, reciprocablemotor means within said forward hull portion for actuating saidhydrofoil between an upper cruising position and a lower takeoffpostion, propulsion means carried by the after end of said forward hullportion in alignment with said hydrofoil, an aerodynamic lifting surfaceon the underside of the main hull portion, said lifting surface havingtwo sections in tandem, each section having an upwardly and aftwardlyextending forward portion, a substantially horizontal intermediateportion and a downwardly and aftwardly sloping rear portion with theportions being blended together to provide a concave curvilinear surfacecreating an upwardly acting aerodynamic force in response to flow of airtherealong, a pair of sponsons extending downwardly on opposite sides ofsaid hull alongside said lifting surface to form a tunnel therewith, apair of hydrofoils pivotally mounted in recesses under the forward endsof said sponsons, reciprocable motor means within said sponsons formoving said last-mentioned hydrofoils between cruising and takeoffpositions, fixed flange type hydroplanes secured to the undersides ofsaid sponsons and extending therealong in alignment with saidlast-mentioned hydrofoils, and a pair of propulsion units at the ends ofsaid sponsons and in alignment with said hydroplanes.
 13. A watercraftcomprising an elongated hull, an undersurface on said hull having aconcavely curved aerodynamic lifting shape configured to provide anupwardly acting force applied to said craft in response to flow of airtherealong, stabilizing fin means carried by laterally spaced portionsof said hull below said aerodynamic lifting surface, each of saidlast-mentioned hull portions carrying said stabilizing fin means at itslower end, each of said stabilizing fin means having a generally flathorizontal lateral configuration in cross section with exposeddownwardly facing and upwardly facing surfaces extending laterallyoutwardly on opposite sides of said lower end, and propulsion meanscarried by said hull, said aerodynamic lifting surface comprising aplurality of surface sections extending from front to rear each surfacesection comprising an upwardly and aftwardly sloping forward portion, asubstantially horizontal intermediate portion, and a downwardly andaftwardly sloping rearward portion, said surface sections beinglongitudinally aligned with one another and located between saidlaterally spaced hull portions, with said portions being blendedtogether in curvilinear fashion and each surface section connected withthe preceding surface section by a substantially horizontal intermediatesection.